Nuclear Magnetic Resonance Solution Structure of the Human Hsp40 (HDJ-1) J-domain

Qian, Yan Qiu; Patel, Dinshaw J.; Hartl, F. Ulrich; McColl, Damian J.

doi:10.1006/jmbi.1996.0394

Cited by 152 publications

(132 citation statements)

References 39 publications

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“…It is also consistent with a reduced association between E1 and the p21-40 H34Q peptide or the full-length YDJ1 H34Q protein (Fig. 4 and data not shown), in agreement with the structural information that suggests helix II and the HPD motif to be the minimal sequences required for Hsp40 in interaction with Hsp70 (25). Thus, the effects of Hsp40 on E1 binding to ori appear to be 2-fold.…”

Section: Discussionsupporting

confidence: 85%

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Human Hsp70 and Hsp40 Chaperone Proteins Facilitate Human Papillomavirus-11 E1 Protein Binding to the Origin and Stimulate Cell-free DNA Replication

Liu¹,

Kuo²,

Makhov

et al. 1998

Journal of Biological Chemistry

106

109

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Human papillomavirus replication initiator, the E1 helicase, binds weakly to the origin of DNA replication. Purified human chaperone proteins Hsp70 and Hsp40 (HDJ-1 and HDJ-2) independently and additively enhanced E1 binding to the origin. The interaction between E1 and Hsp70 was transient and required ATP hydrolysis, whereas Hsp40 bound to E1 directly and remained in the complex. A peptide of 20 residues spanning the HPD loop and helix II of the J domain of YDJ-1 also stimulated E1 binding to the origin, alone or in combination with Hsp70 or Hsp40. A mutated peptide (H34Q) had a reduced activity, while an adjacent or an overlapping peptide had no effect. Neither Hsp70 nor the J peptide altered the E1/DNA ratio in the complex. Electron microscopy showed that E1 mainly bound to DNA as a hexamer. In the presence of Hsp40, E1 primarily bound to DNA as a dihexamer. Preincubation of chaperones with viral E1 and template shortened the lag time and increased replication in a cell-free system. Since two helicases are essential for bidirectional replication of human papillomavirus DNA, these results demonstrate that, as in prokaryotes, chaperones play an important role in the assembly of preinitiation complexes on the origin.Molecular chaperones regulate many cellular processes such as protein folding and translocation and the assembly and disassembly of multiprotein complexes (reviewed in Ref. 1). Two major Escherichia coli chaperones DnaK and DnaJ were originally identified as genes required for the initiation of bacterial or bacteriophage DNA replication. Mutations in DnaK and DnaJ lead to defects in DNA and RNA synthesis, cell division, and proteolysis (for reviews, see Refs. 2-4). DnaK is a weak ATPase with the ability to bind unfolded polypeptides (5, 6). DnaJ functions as a dimer (7, 8) and is considered a cochaperone, since it dramatically stimulates the ATPase activity of DnaK in the presence of GrpE (6, 9). Together, these proteins facilitate the binding of the replication initiator protein to the origin (ori) and the initiation of DNA replication (Ref. 7; for reviews, see .The families of eukaryotic heat shock protein 70 (Hsp70/ Hsc70) and heat shock protein 40 (Hsp40) have a high degree of homology to DnaK and DnaJ, respectively. Hsp70 and Hsp40 proteins are co-localized to the cytosol and also function in the nucleus (15, 16). As in prokaryotes, the Hsp40 proteins function as co-chaperones of Hsp70, but they also have weak, independent activity (5,7,(17)(18)(19)(20). All of the DnaJ homologues, such as HDJ-1, HDJ-2, and YDJ-1, members of the human and yeast Hsp40 family, have a conserved J domain at the amino terminus. Truncated E. coli or YDJ-1 containing only the J domain is sufficient to modulate the ATPase activity of DnaK/Hsp70 (20, 21). The corresponding J domain of the human Hsp40 proteins is also thought to mediate interactions with Hsp70 and regulate its ATPase activity (for a review, see Ref. 8). Within the J domain, there is a highly conserved HPD tripeptide loop flanked by two ␣-helices, designat...

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Section: Discussionsupporting

confidence: 85%

“…8). Within the J domain, there is a highly conserved HPD tripeptide loop flanked by two ␣-helices, designated helix II and helix III (22)(23)(24)(25). Mutations in the HPD motif or in the external faces of the ␣-helices significantly reduce its activity (21, 26 -28).…”

mentioning

confidence: 99%

Human Hsp70 and Hsp40 Chaperone Proteins Facilitate Human Papillomavirus-11 E1 Protein Binding to the Origin and Stimulate Cell-free DNA Replication

Liu¹,

Kuo²,

Makhov

et al. 1998

Journal of Biological Chemistry

106

109

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“…However, the divergence is similar to the difference seen with the J domains of simian virus 40 (SV40) and other polyomaviral T antigens, which can functionally substitute for the DnaJ J domain in E. coli (Kelley and Georgopoulos, 1997). Furthermore, secondary structure prediction for AHM1 did not deny the folding pattern resolved with J domain polypeptides derived from DnaJ and human Hdj-1 (Pellecchia et al, 1996;Qian et al, 1996). In particular, hydrophobic residues participating in the formation of a short coiled-coil between helices II and III and the three-amino acid sequence HPD in the resulting loop are well conserved ( Figure 2A).…”

Section: Ahm1 I a Member Of The Plant-specific J Domain Protein Subfamentioning

confidence: 92%

AHM1, a Novel Type of Nuclear Matrix-Localized, MAR Binding Protein with a Single AT Hook and a J Domain-Homologous Region

Morisawa¹,

Han-yama²,

Moda³

et al. 2000

The Plant Cell

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Interactions between the nuclear matrix and special regions of chromosomal DNA called matrix attachment regions (MARs) have been implicated in various nuclear functions. We have identified a novel protein from wheat, AT hookcontaining MAR binding protein1 (AHM1), that binds preferentially to MARs. A multidomain protein, AHM1 has the special combination of a J domain-homologous region and a Zn finger-like motif (a J-Z array) and an AT hook. For MAR binding, the AT hook at the C terminus was essential, and an internal portion containing the Zn finger-like motif was additionally required in vivo. AHM1 was found in the nuclear matrix fraction and was localized in the nucleoplasm. AHM1 fused to green fluorescent protein had a speckled distribution pattern inside the nucleus. AHM1 is most likely a nuclear matrix component that functions between intranuclear framework and MARs. J-Z arrays can be found in a group of (hypothetical) proteins in plants, which may share some functions, presumably to recruit specific Hsp70 partners as co-chaperones. INTRODUCTIONThe nuclear matrix, operationally defined, is the dynamic fibrogranular structure forming the skeletal framework that surrounds and penetrates the interphase nucleus; it has been implicated in most nuclear functions, including replication, repair, transcription, RNA processing, and RNA transport (Berezney and Jeon, 1995). The chromosomal DNAs are known to be associated with the nuclear matrix at specific regions called matrix attachment regions (MARs) and are thereby thought to be organized into topologically constrained loops, each of which represents a sort of functional or structural domain (or both) (Laemmli et al., 1992;Bode et al., 1996). In animals, interactions between the nuclear matrix and MARs have also been shown to be involved in DNA replication and repair and in various aspects of gene regulation, thus playing a key role in the essential functions of the nucleus (Boulikas, 1995;Bode et al., 1996).MARs consist of AT-rich sequences extending over at least a few hundred base pairs and containing various ATrich motifs as well as structural motifs such as base-unpairing regions and intrinsically curved portions (Boulikas, 1995). In animals, MAR binding activity has been found in a wide range of structurally and functionally diverse proteins (listed in Boulikas, 1995). These include topoisomerase II (Adachi et al., 1989); filament proteins such as lamins and NuMA (Ludérus et al., 1992(Ludérus et al., , 1994; ARBP, identical to a methylated CpG binding protein (von Kries et al., 1991;Weitzel et al., 1997); hnRNP-U/SAF1, an RNA binding protein involved in RNA processing (Fackelmayer et al., 1994;von Kries et al., 1994); SATB1, a tissue-specific transcription factor with high affinity for base-unpairing regions (Dickinson et al., 1992; de Belle et al., 1998); and architectural chromatin proteins such as histone H1 and HMG-I/Y (Zhao et al., 1993).In plants, MARs have been found in intergenic regions, often in or close to the regulatory regions of genes, and clo...

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“…Hence, Hsc70 is a heterotropic allosteric system. The allosteric process is enhanced by the cochaperones HdJ (enhances protein substrate binding and ATP hydrolysis) (8) and the nucleotide factor BAG-1 (enhances ADP to ATP exchange; ref. 9).…”

mentioning

confidence: 99%

The 70-kDa heat shock protein chaperone nucleotide-binding domain in solution unveiled as a molecular machine that can reorient its functional subdomains

Zhang

Zuiderweg

2004

Proc. Natl. Acad. Sci. U.S.A.

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The 70-kDa heat shock cognate (Hsc70) chaperone plays a crucial role in protein (re-)folding and triage in the mammalian cytosol. Here we study, by NMR, the 44-kDa nucleotide-binding domain (NBD) of this molecule, which allosterically regulates, by binding either ADP or ATP in a cleft between the two main lobes, the chaperoning affinity of the attached substrate-binding domain. The NBD is also a center of interaction with cochaperones that couple into the allostery. By measuring residual dipolar couplings by NMR, we show that the orientation of two lobes of the Hsc70 NBD in solution deviates up to 10°from their positions in 14 superimposing x-ray structures. Additional orientational differences of subdomains within the lobes unveil the Hsc70 NBD in solution as a flexible molecular machine that can adjust the relative positions of all of its four subdomains. Because the residues interacting with the nucleotide emanate from all four subdomains, adjustments in subdomain orientation should affect the nucleotide chemistry and vice versa. Our data suggest a hypothesis that cochaperone or substrate domain binding perturbs the relative subdomain orientations, thereby functionally and allosterically coupling to the nucleotide state of the NBD. The 70-kDa heat shock protein (Hsp70) chaperones are conserved from bacteria to mammals and are the main facilitators of protein folding, refolding, and trafficking (1). In this process, they are assisted by several cochaperones. Mammalian Hsp70's have additional roles in activation of transcription factors, protein kinases, antigen presentation, tumor immunogenicity, and ribosome assembly (2). In humans, the constitutively expressed cytosolic form is Hsc70 (heat shock cognate). Hsc70 is functionally coupled to the proteolytic and apoptotic cascades placing it at the center of protein triage (3).Hsc70 is a 70-kDa monomer, for which no complete structure has been obtained. It consists of three domains, which were solved individually. There is an N-terminal 44-kDa nucleotidebinding domain (NBD), which is solved by crystallography, and is the focus of this report (4). A 15-kDa substrate-binding domain (SBD), connected to the NBD by a 6-10 hydrophobic residue, harbors the substrate-binding cleft that binds exposed hydrophobic sequences in misfolded substrate proteins, and was solved in different forms and species by crystallography and NMR (5, 6). A subsequent 10-kDa domain of ␣-helical lid structure tunes the kinetics of substrate binding and release (7). ATP binding at the NBD promotes release of the protein substrate from the SBD; protein substrate binding at the SBD promotes the hydrolysis of ATP in the NBD. Hence, Hsc70 is a heterotropic allosteric system. The allosteric process is enhanced by the cochaperones HdJ (enhances protein substrate binding and ATP hydrolysis) (8) and the nucleotide factor BAG-1 (enhances ADP to ATP exchange; ref. 9). Many other factors bind to Hsc70 as well.In the NBD, one recognizes two main lobes (see the legend to Fig. 1 for residue counts). Within th...

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Nuclear Magnetic Resonance Solution Structure of the Human Hsp40 (HDJ-1) J-domain

Cited by 152 publications

References 39 publications

Human Hsp70 and Hsp40 Chaperone Proteins Facilitate Human Papillomavirus-11 E1 Protein Binding to the Origin and Stimulate Cell-free DNA Replication

Human Hsp70 and Hsp40 Chaperone Proteins Facilitate Human Papillomavirus-11 E1 Protein Binding to the Origin and Stimulate Cell-free DNA Replication

AHM1, a Novel Type of Nuclear Matrix-Localized, MAR Binding Protein with a Single AT Hook and a J Domain-Homologous Region

The 70-kDa heat shock protein chaperone nucleotide-binding domain in solution unveiled as a molecular machine that can reorient its functional subdomains

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